Over the last two decades, amorphous alloys, or metallic glasses, have received increasing attention because of their unique characteristics, such as high strength, high specific strength, large elastic strain limit, excellent wear and corrosion resistance, along with other remarkable engineering properties. Because of the promise shown by these materials, researchers have designed a multitude of multi-component systems that form amorphous glassy alloys, among which Zr-based bulk metallic glasses (“BMGs”) have been utilized commercially to produce a variety of items, including, for example, sporting goods, electronic casings, and medical devices.
However, the same high hardness, high corrosion resistance, and high fracture resistance are properties that make this class of materials desirable can also make the post-fabrication processing of these materials difficult. For example, because BMG are highly resistant to chemical corrosion, a strong, very corrosive etchant would be needed for etching. Likewise, because metallic glasses have very high hardness and strength, more energy would be needed to process mechanically the metallic glasses, such as, for example, polishing, grinding, and punching a hole. This issue can become particularly challenging when only a small portion of a part made of a metallic glass is to be processed (e.g., machined). Namely, while one might want to weaken the small portion of the metallic glass part to facilitate processing, one would not want to alter the part as a whole to sacrifice the desired properties of the metallic glass.
Thus, a need exists to selectively create regions on a metallic glass part with a different property than the remainder of the part, so that the localized difference in material property can facilitate the processing of the part.